Toolchain/binutils-gdb
1
0
Fork 0
forked from Imagelibrary/binutils-gdb
Code Pull Requests Activity

libctf: archive: allow opening BTF dicts in archives (not for upstreaming)

Browse Source 
BTF dicts are normally suppressed in archives, but it is possible
to create them with enough cunning.  If such an archive is
encountered, the BTF dicts in it have no parent name, which
means that ctf_arc_import_parent (used by ctf_dict_open_cached,
ctf_archive_next, and all the ctf_arc_lookup functions) fails
to figure out what parent to import, and fails.

Kludge around it by relying on our secret knowledge that ctf_link_write
always emits the parent dict into the archive first.  If no name is set,
import the parent dict for now.  (Before upstreaming, a new archive format
with a dedicated parent dict field will turn up, obviating this kludge.)
This commit is contained in:
Nick Alcock
2025-04-25 21:09:34 +01:00
parent 88f2c13d1c
commit 918e356b18
1 changed files with 23 additions and 3 deletions
Download Patch File Download Diff File Expand all files Collapse all files

26
libctf/ctf-archive.c
View File

@@ -839,11 +839,31 @@ ctf_arc_open_by_name_sections (const ctf_archive_t *arc,
static int
ctf_arc_import_parent (const ctf_archive_t *arc, ctf_dict_t *fp, int *errp)
{
if ((fp->ctf_flags & LCTF_CHILD) && fp->ctf_parname && !fp->ctf_parent)
if ((fp->ctf_flags & LCTF_CHILD) && !fp->ctf_parent)
{
int err;
ctf_dict_t *parent = ctf_dict_open_cached ((ctf_archive_t *) arc,
fp->ctf_parname, &err);
ctf_dict_t *parent;
const char *parent_name = fp->ctf_parent_name;
/* If no parent is set, and this is an archive, assume that the parent
is the first dict in the archive, which matches what ctf_link
produces. UPTODO: add a dedicated header entry for parent
name. */
if (!parent_name && arc->ctfi_archive)
{
struct ctf_archive_modent *modent;
const char *nametbl;
modent = (ctf_archive_modent_t *) ((char *) arc->ctfi_archive
+ sizeof (struct ctf_archive));
nametbl = (((const char *) arc->ctfi_archive)
+ le64toh (arc->ctfi_archive->ctfa_names));
parent_name = &nametbl[le64toh (modent[0].name_offset)];
}
parent = ctf_dict_open_cached ((ctf_archive_t *) arc, parent_name, &err);
if (errp)
*errp = err;